Environmental chiefs have been called in to investigate the discovery of blood in a Teesside beck.

Foul water from a combined sewer pipe poured in to Lustrum Beck in Hartburn, Stockton, yesterday.

Police were first called to the scene at 12.30pm. Initial checks confirmed the substance was blood, but not human.

The investigation has been passed on to Northumbrian Water and the Environment Agency.

A spokeswoman for Northumbrian Water said the blood appeared to be coming from a combined sewer which was carrying foul water and service water.

She said: "Because of the heavy rainfall recently, it is being diluted as soon as it is entering the beck. We are working with the Environment Agency to establish where is it coming from."

A spokeswoman for the Environment Agency said: "We are investigating the incident and until we are finished we cannot confirm where the blood has come from. We are working with Northumbrian Water to find out who is responsible for the problem and will then deal with those concerned."